Field of the Invention
The present invention relates to a measurement apparatus for measuring the shape of the surface of an object, and a measurement method.
Description of the Related Art
As disclosed in Japanese Patent Laid-Open No. 10-19504, there is known a measurement apparatus for measuring the shape of the surface of an object by scanning a probe on the surface of the object. Such measurement apparatus can measure the shape of the surface of the object by, for example, providing a reference member, and detecting the distance between the reference member and the probe while scanning the probe on the surface of the object.
In recent years, along with an increase in size of the surface of the object, it has been necessary to enlarge the scanning range of the probe in the measurement apparatus. As a method of enlarging the scanning range of the probe, for example, there is provided a method of arranging a plurality of reference members in the scanning direction of the probe. If, however, a plurality of reference members are used, a reference member whose distance to the probe is to be detected is changed depending on scanning of the probe. Consequently, it is difficult to accurately measure the shape of the surface of the object. For example, the measurement result of the shape of the surface of the object becomes discontinuous between the plurality of reference members.